The present invention relates to a slider for a zip fastener.
As known in prior art, the slider of the zip fastener is a part which is formed by a slider body and a pull tab and which moves on the zip fastener. The slider opens the zip fastener by separating opposite rows of teeth from each other and, in a corresponding manner, closes the zip fastener by engaging the rows of teeth with each other. The slider of the zip fastener generally comprises 2 to 5 components. Since the slider of the zip fastener is formed of small, separate components, it always involves a separate assembly operation, which is complicated and time-consuming and thus it also increases manufacturing costs.
In prior art there are known many types of zip fastener sliders which are conventionally divided into the groups: retainer sliders, which include automatic lock sliders and pin lock sliders, and non-retainer sliders. Different zip fastener types are described, for example. in the SFS Standard 4330 xe2x80x9cSlide fasteners. Terminology and definitionsxe2x80x9d.
In the applications known in prior art, for example, the tab holder part of the slider on the zip fastener must be bent to bring the pull tab of the zip fastener into its position because, in the assembly stage of the zip fastener, the tab holder of the body is open and the pull tab is threaded into its position and after that the tab holder is pressed to its proper position. In automatic lock sliders and pin lock sliders, many different arrangements are known in which the locking operation is provided by means of small spring parts and the like.
Finding a separate slot in the zip fastener itself for the tip of a locking pin or a locking spring in the zip fastener itself is usually a problem in the prior art sliders provided with a retainer.
An object of the invention is to provide a zip fastener slider which is simple in structure and in its mode of assembly yet offers numerous possibilities of producing different lock types.
An object of the invention is to provide a zip fastener slider having a pull tab which remains in connection with the slider when the zip fastener is in place in the slider of the zip fastener.
It is also an object of the invention to provide a zip fastener slider whose tab holder need not be bent for disposing a pull tab in place in connection with manufacture.
It is also a further object of the invention to provide a zip fastener slider which is provided with a retainer and in which locking operates without a slot intended for the tip of a locking pin or a locking spring in the zip fastener.
An important object of the invention is also to provide a zip fastener slider in which a spring effect is produced without a spring. In prior art there is known a xe2x80x9cpin lockxe2x80x9d whose pin tip is rounded, but in that connection a tooth made of metal or another material is pressed against the zip fastener without a spring effect, with the result that the operation of locking is forced. In these known applications, finding a slot in the zip fastener for the locking tip is problematic because it is difficult to find it and it may break the zip fastener.
What is new and inventive in the zip fastener slider in accordance with the invention is particularly that the pull tab is threaded into its position through a threading gap/threading point between the tail of a tab holder/the tail of a rail part and the body of the slider outside the body of the slider and the throat of the slider. The zip fastener slider in accordance with the invention provides numerous locking alternatives for the zip fastener slider, the flexibility of which alternatives is easily and reliably adjustable, by placing the threading point/threading gap, a retainer head, a snap point and/or textile material in the ways in accordance with the different embodiments of the invention. The flexibility of the zip fastener slider in accordance with the invention and its applicability to different types of locking alternatives can thus be adjusted and accomplished without separate spring parts and the like and without a hole intended for a locking pin in the cover plate (upper cover) of the slider.
It is the wide range of locking in particular that is new and inventive in the zip fastener slider in accordance with the invention. By means of the zip fastener slider in accordance with the invention, locking can be provided by pressing a locking head into some suitable slot or against a locking surface, which can be the surface of a tooth or the surface of the entire tooth system or the surface of a textile tape, the surface of the textile tape outside the tooth system or the sides of the tooth system may even be used.
In accordance with the invention, a spring effect without a spring is produced by means of a snap slot located under a tab holder or a rail or by means of another equivalent recess. The spring effect can also be produced by means of a retainer head. The retainer head can be made of a hard or flexible material or it can be shaped to be flexible.
When the pressing stage of the retainer head takes place outside the throat of the slider, a smaller or greater spring effect is produced in which the tab holder can behave flexibly, in which the retainer head can behave flexibly and in which the zip fastener 10 behaves flexibly, which flexible behaviours and the dimensioning of lever arms serve to provide a locking head that is positioned beyond the dead centre. This kind of locking can be absolutely tight, while, for example, the prior art locking accomplished by a spring is hardly ever so tight; or it can be even very light locking according to the need of dimensioning in each particular case.
It is not necessary to use more than one of the above-mentioned flexible elements at a time.
In accordance with the invention, a spring effect is produced without a spring by shaping the members of the slider of the zip fastener in a suitable manner. In accordance with the invention, for example, under the tab holder there is a snap slot or the tab holder or the retainer head of the pull tab is shaped to be flexible or the retainer head is made of a flexible material. It is also possible to produce the spring effect such that the zip fastener is made flexible within the throat of the zip fastener slider, for example, by making a hole in the lower cover of the zip fastener slider, thereby producing a spring effect without a spring made of a steel or other material. Thus, in accordance with the invention, compression locking is achieved in a simple manner and which does not cause any problems in finding a locking location for the zip fastener and does not damage the zip fastener. The spring effect in accordance with the invention is also operative inside the top plate and the throat of the zip fastener slider.
In accordance with one embodiment of the invention, a slider for a zip fastener is provided in which locking operates outside the cover plate without an opening (hole) in the cover plate.
Further, in accordance with one embodiment of the invention, a slider for a zip fastener is provided in which locking operates by pressing the zip fastener outside or from outside the rear of the slider throat and in which said pressing force and location can be adjusted by dimensioning, shaping, and selection of materials of the parts, without a spring usually needed in the sliders of zip fasteners.
In accordance with one embodiment of the invention, a slider for a zip fastener is provided in which the location of pressing may be any part of the zip fastener. The location may be teeth of the zip fastener, a gap in the teeth, or pressing may be directed at edges of the teeth or at both the teeth and the textile tapes of the zip fastener or even at the textile tapes of the zip fastener alone.
The zip fastener slider in accordance with the invention is simple in construction and in its mode of assembly, and it is substantially formed of two parts: a slider body and a pull tab. A tab holder part formed in connection with the slider body enables the pull tab to be fastened in place. The tab holder part may be formed such that below it and between the top plate of the slider body there remains a space in which the loop portion of the pull tab is located when the loop of the pull tab has been threaded into place around the tab holder part of the slider body. The tab holder part may also be formed so that it is rail-shaped, in which case it comprises a tab-holder-like enlarged portion and a narrower rail portion which is attached to the top plate of the slider body. In that connection, the loop of the pull tab is formed to be clamp-like and the clamp parts are pressed to the rail part on both sides of it and the loop portion is substantially around the enlarged portion. A threading gap/threading point for the pull tab is formed in connection with the tab holder part in the slider body of the zip fastener such that the pull tab cannot fall off when the zip fastener is in place in the slider body. The threading gap/threading point is placed substantially outside the top plate, advantageously at the rear of the slider with respect to the running direction of the slider closing the zip fastener, i.e. viewed in the horizontal plane from outside the rear of the top plate.
In accordance with the invention, the pull tab is primarily prevented from coming off the slider by the placement of the zip fastener in position in the slider and, in accordance with one advantageous embodiment of the invention, the zip fastener substantially closes the threading gap of the pull tab formed between the tail part of the tab holder part of the slider and the top plate of the slider. The tab holder of the slider need not be bent at the assembly stage of the slider because the pull tab can be passed between the slider body and the tab holder into its position as the end part of the tab holder extends so that it is at a distance from the rear end of the slider body, i.e. from the rear of the slider with respect to the running direction of the slider closing the zip fastener, in which connection there remains a space between them, that is, a threading gap for threading the loop of the pull tab into place. When the slider is in place, the tail part of the tab holder extends to the substantial vicinity of the zip fastener, in which connection the pull tab is not able to fall away from its place.
In accordance with one advantageous embodiment of the invention, a rail-shaped tab holder part is formed on the body of the zip fastener slider, a threading point for the pull tab being formed in connection with said tab holder part such that the threading point extends outside the slider body such that the zip fastener situated in place in the slider body prevents the pull tab from falling away from its place but the pull tab can be easily threaded into place before the zip fastener is inserted in the slider body. The tab holder part has thus been formed into a rail, in which connection the tab holder part comprises an outer enlarged portion and which in the front part of the zip fastener extends to the slider body and in the rear part forms an edge part of a threading gap and the rail part of which is substantially narrower than the enlarged part, forming a rail on which a clamp-like pull tab is arranged to be moved and onto which portion the pull tab is passed through the threading point. In this exemplifying embodiment of the invention, the threading portion of the pull tab in the rail part has been so shaped that the pull tab is not able to fall away from its place when the zip fastener is in place in the slider body of the zip fastener. The tab holder part of the body and the pull tab have been so shaped that the threading point of the pull tab formed between the slider body and the tail part of the tab holder part extends close to the zip fastener so that the pull tab remains in connection with the slider body when the zip fastener is in place in the slider of the zip fastener.
In accordance with one advantageous further feature of the invention, in the case of zip fastener sliders provided with a retainer, the locking of the slider onto the zip fastener is most advantageously arranged so that the retainer head of the pull tab is pressed against the zip fastener, and the locking force required in the zip fastener slider, the snapping of the pull tab into a locking position and away from the locking position, can be adjusted by displacing the locking points or by shaping the lower surface of the tab holder/rail part or by making use of the stiffness or bending of the zip fastener outside the throat of the slider or by the choice, stiffness and bending of the material of the pull tab itself. The locking of the slider can be easily adjusted for different purposes and chain types by shaping, for example, the retainer head of the pull tab or other parts of the slider according to each particular need. By displacing the locking point, a fully locking version can be made into an arrangement in which the locking holds only up to a certain desired limit. In that case, the zip fastener does not break even under a heavy load but yields when the load becomes too high. In accordance with one advantageous additional feature of the invention, locking is arranged mainly between the locking tip of the retainer in the pull tab and the bottom cover of the slider outside or from outside the rear of the cover plate (upper cover) (not through the cover plate, as locking is generally accomplished).
The slider for a zip fastener in accordance with the invention is suitable for use both in zip fasteners sliders provided with a retainer and in those without a retainer.
The zip fastener slider in accordance with the invention is particularly reliable in operation because the pull tab comes off and can generally be detached only when the tooth part of the zip fastener itself has not been threaded inside the slider. In accordance with some advantageous embodiments of the invention, by bending the tab holder or by shaping the tab holder/rail, it is also possible to ensure that the pull tab will not come off. A corresponding effect can be achieved by shaping the pull tab or the body part or by arranging the shapes of the body part and the tab holder/rail part to fit together in a desired manner.
In one advantageous embodiment of the invention, further by using a small spring as a member closing the threading gap, a zip fastener slider can be provided into which a pull tab can be passed, for instance, afterwards. A corresponding effect is also achieved by arranging a small spring or a flexible point on the side of the pull tab.
In all of these advantageous embodiments of the invention, the arrangement is simple and the locking itself is located outside the top part, i.e. the top plate, of the slider body. By this means it is possible to avoid the difficulties and limitations caused in the locking which takes place through the top plate.
In accordance with an advantageous feature of the invention, a locking tip can be arranged inside the top plate of the slider of the zip fastener, but in this arrangement locking takes place from outside the rear of the top plate and not through an opening in the top plate.
The invention can also be applied to many other needs, for example, a slider in which a rail part is used instead of a tab holder part can easily be made two-sided, in which case it can be used in reversible clothes and in other similar products.
The slider for a zip fastener in accordance with the invention is simpler in construction than prior art sliders, so that the manufacturing costs of the zip fastener slider are lower than those of prior art zip fastener sliders.